1. A switch assembly comprising:
a switch housing;
an elongate actuator shaft projecting inwardly into said switch housing, said actuator shaft being axially displaceable between three predetermined switch positions;
a magnet mounted to said actuator shaft, said magnet being positioned within said housing at separate predetermined locations that correspond on a one-to-one basis with said three predetermined switch positions;
first and second magnetic reed switches, said first and second magnetic reed switches being mounted at locations within said housing relative to said elongate actuator shaft and said magnet to place said magnet at locations that cause said first and second reed switches to be in a first open-closed circuit operational state when said switch is in the first of said three predetermined switch positions, to be in a second open-closed circuit operational state when said switch is in the second of said three predetermined switch positions, and to be in a third open-closed operational state when said switch is in the third of said three predetermined switch positions.
2. The switch assembly of claim 1, wherein the inward and outward displacement of said actuator shaft are limited to a predetermined distances, said magnet being located centrally between said inward and outward displacement limits of said actuator shaft when said switch assembly is in said first position, said actuator shaft being at its outward displacement limit when said switch assembly is in said second position, and said actuator shaft being at its inward displacement limit when said switch assembly is in said third position, and wherein said switch assembly further comprises a spring-loaded detent mechanism for maintaining said switch assembly in said first position in the absence of an inward or outward force sufficient to move said actuator shaft toward said second or third position, said spring-loaded detent mechanism returning said switch assembly to said first switch position location when said switch assembly is actuated to one of said second switch positions and the actuation force is removed.
3. The switch assembly of claim 2, wherein the spring-loaded detent mechanism comprises first and second contoured bearing surfaces and first and second spring-loaded plunger assemblies, said first and second contoured bearing surfaces being oppositely disposed from one another and extending inwardly into said actuator shaft at a location that establishes said first position of said switch assembly, said first and second spring-loaded plunger assemblies each including a spring, a cylindrical roller, and a plunger having first and second ends, said roller being mounted for rotation at the first end of said plunger, said first and second plungers being respectively received for sliding movement in first and second recesses that are formed in the interior of said switch housing and are located at a position adjacent said first and second contoured bearing surfaces when said switch assembly is in said first switch position, each said first and second recess having a wall at one end thereof with the second end being open and facing said actuator to position the roller associated with the plunger next to said actuator shaft, said spring of each said spring-loaded plunger assembly being located between said wall of said recess the plunger contained in said recess to urge the roller associated with said plunger against said actuator shaft.
4. The switch assembly of claim 3, wherein the contour of said contoured bearing surfaces and the force asserted by said spring-loaded plungers establish a force-displacement relationship in which the force required to move said elongate actuator shaft from first switch position toward one of said second and third switch positions varies as a function of displacement distance, with the force required for initial displacement being greater than the force required for continued displacement.
5. The switch assembly of claim 4, wherein the force-displacement relationship of said contoured bearing surfaces and said spring-loaded plungers are established so that more force is required to axially displace said elongate actuator shaft toward one of said second and third switch positions than is required to displace said elongate switch actuator shaft toward the other of said second and third switch positions.
6. The switch assembly of claim 1 further comprising a circuit board mounted within said switch housing in spaced apart juxtaposition with said actuator shaft, said first and second reed switches being mounted to said circuit board at said locations that cause said first and second reed switches to be in a first open-closed circuit operational state when said switch is in the first of said three predetermined switch positions, to be in a second open-closed circuit operational state when said switch is in the second of said three predetermined switch positions, and to be in a third open-closed operational state when said switch is in the third of said three predetermined switch positions.
7. The switch assembly of claim 6 wherein said first and second magnetic reed switches are connected in series with one another and wherein said circuit board includes first and second electrical terminals, said switch assembly further comprising first, second and third resistors, with said first resistor being electrically connected between said first electrical connector and one of said first and second series connected magnetic reed switches, said second electrical terminal being electrically connected to the second one of said first and second magnetic reed switches, said second resistor being electrically connected in parallel with said first magnetic reed switch and said third resistor being electrically connected in parallel with said second magnetic reed switch.
8. The switch assembly of claim 7 wherein said switch housing includes a receptacle for receiving an electrical connector and said first and second electrical terminals extend outwardly from said circuit board to form electrical contacts that mate with electrical contacts of said electrical connector.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A transparent pane comprising
an electrically heatable coating electrically connected to at least two first electrodes provided for electrical connection to two terminals of a voltage source such that by applying a feed voltage, a heating current flows over a heating field formed between the at least two first electrodes,
wherein the heating field includes at least one coating-free zone, which is bounded by a zone edge formed at least in sections by the electrically heatable coating, characterized by at least one second electrode provided for electrical connection to one of the two terminals of the voltage source, the at least one second electrode having at least one supply section disposed at least in sections in the at least one coating-free zone and at least one connection section connected to the at least one supply section, and
wherein the at least one connection section extends starting from the at least one coating-free zone, beyond an edge section of the zone edge, the edge section being formed by a section of the heating field that is situated between the at least one coating-free zone and the at least two first electrodes provided for connection to a second one of the two terminals of the voltage source.
2. The transparent pane according to claim 1, wherein the at least one connection section is provided with a free end.
3. The transparent pane according to claim 1, wherein the at least one connection section is evenly distributed over the edge section of the at least one coating-free zone.
4. The transparent pane according to claim 1, wherein the at least one supply section is composed of a coating portion disposed outside the at least one coating-free zone and a zone portion disposed within the at least one coating-free zone.
5. The transparent pane according to claim 1, wherein the at least one supply section is disposed completely within the at least one coating-free zone.
6. The transparent pane according to claim 1, wherein the at least one supply section follows at least the edge section of the zone edge, beyond which the at least one connection section extends.
7. The transparent pane according to claim 1, wherein the at least one supply section circumferentially follows the zone edge.
8. The transparent pane according to claim 1, wherein the at least one supply section is distributed disposed over the at least one coating-free zone.
9. The transparent pane according to claim 1, wherein the at least one second electrode has at least two supply sections, which are connected to the at least one connection section.
10. The transparent pane according to claim 1, wherein the at least one second electrode has a resistance such that upon applying the feed voltage, the heating current flowing through the heating field has an at least approximately homogeneous current density distribution.
11. The transparent pane according to claim 10, wherein a length of the at least one supply section is dimensioned such that the at least one second electrode has a predefinable electric resistance.
12. The transparent pane according to claim 1, wherein the at least one supply section consists of at least two supply parts separated from each other, which have respective coupling sections electrically connected to the electrically heatable coating, the two coupling sections being disposed such that they are galvanically coupled by the electrically heatable coating.
13. The transparent pane according to claim 12, wherein the two coupling sections have an approximately parallel course.
14. The transparent pane according to claim 12, wherein a first coupling section is connected to one of the at least two first electrodes provided for connection to one of the two terminals of the voltage source and a second coupling section is connected to the at least one connection section.
15. A method for producing manufacturing a transparent pane, comprising:
producing providing an electrically heatable coating,
forming at least two first electrodes provided for electrical connection to two terminals of a voltage source, the at least two first electrodes being electrically connected to the electrically heatable coating such that by applying a feed voltage, a heating current flows over a heating field situated between the at least two first electrodes,
producing providing at least one coating-free zone in the heating field, the at least one coating-free zone being bounded by a zone edge formed at least in sections by the electrically heatable coating, and
producing providing at least one second electrode provided for electrical connection to one of the two terminals of the voltage source, which the at least one second electrode having at least one supply section disposed at least in sections in the at least one coating-free zone and at least one connection section connected to the at least one supply section,
wherein the at least one connection section extends, starting from the at least one coating-free zone, beyond an edge section of the zone edge, and
wherein the edge section is formed by a section of the heating field, which is situated between the at least one coating-free zone and one of the at least two first electrodes provided for connection to the other one of the two terminals of the voltage source.
16. The transparent pane according to claim 3 wherein two or more connection sections are implemented like a comb.
17. The transparent pane according to claim 11, wherein the predefinable electric resistance is equivalent to the sheet resistance of the heatable coating in a surface area that corresponds to the at least one coating-free zone